During volcanic eruptions ascending magma undergoes decompression, resulting in a decrease of dissolved H2O. This creates unstable conditions for the hydrous mineral amphibole. As a result a reaction rim forms from anhydrous minerals such as pyroxene, plagioclase, and Fe-Ti oxides (Rutherford and Hill, 1993). There have been numerous studies done...
The origin of hornblendite and other mafic mineral-rich veins found in Cretaceous plutonic rocks from the Northern Cascades is currently not well known. This study seeks to investigate the possible relationship between host plutonic rocks and hornblendite and pyroxene-rich veins by comparing the chemical compositions and petrographic features between the...
The origin of hornblendite and other mafic mineral-rich veins found in Cretaceous plutonic rocks from the Northern Cascades is currently not well known. This study seeks to investigate the possible relationship between host plutonic rocks and hornblendite and pyroxene-rich veins by comparing the chemical compositions and petrographic features between the...
Harrat Hutaymah is an alkali basalt volcanic field in north-central Saudi Arabia, at the eastern margin of a large Neogene continental, intraplate magmatic province. Lava flow, tephra and spatter cone compositions in the field include alkali olivine basalts and basanites. These compositions contrast with the predominantly tholeiitic, fissure-fed basalts found...
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western Saudi Arabia
Robert A. Duncan a,b,⁎, AdamJ.R. Kent a, Carl R. Thornber c, Tyler D. Schlieder a
Extensive volcanic fields on the western Arabian Plate have erupted intermittently over the last 30 Ma following emplacement of the Afar flood basalts in Ethiopia. In an effort to better understand the origin of this volcanism in western Saudi Arabia, we analyzed ³He/⁴He, and He, CO₂ and trace element concentrations...
Full Text:
, Robert A. Duncan a,
AdamJ.R. Kent a, Abdullah M. Al-Amri c
a College of Earth, Ocean, and Atmospheric
Extensive volcanic fields on the western Arabian Plate have erupted intermittently over the last 30 Ma following emplacement of the Afar flood basalts in Ethiopia. In an effort to better understand the origin of this volcanism in western Saudi Arabia, we analyzed ³He/⁴He, and He, CO₂ and trace element concentrations...
Harrat Hutaymah is an alkali basalt volcanic field in north-central Saudi Arabia, at the eastern margin of a large Neogene continental, intraplate magmatic province. Lava flow, tephra and spatter cone compositions in the field include alkali olivine basalts and basanites. These compositions contrast with the predominantly tholeiitic, fissure-fed basalts found...
Harrat Hutaymah is an alkali basalt volcanic field in north-central Saudi Arabia, at the eastern margin of a large Neogene continental, intraplate magmatic province. Lava flow, tephra and spatter cone compositions in the field include alkali olivine basalts and basanites. These compositions contrast with the predominantly tholeiitic, fissure-fed basalts found...
Extensive volcanic fields on the western Arabian Plate have erupted intermittently over the last 30 Ma following emplacement of the Afar flood basalts in Ethiopia. In an effort to better understand the origin of this volcanism in western Saudi Arabia, we analyzed ³He/⁴He, and He, CO₂ and trace element concentrations...
Harrat Hutaymah is an alkali basalt volcanic field in north-central Saudi Arabia, at the eastern margin of a large Neogene continental, intraplate magmatic province. Lava flow, tephra and spatter cone compositions in the field include alkali olivine basalts and basanites. These compositions contrast with the predominantly tholeiitic, fissure-fed basalts found...